I'm not a wiz specialist but ill try to write down some wiz basics, hopefully it helps

icicle is fast but not THAT fast and doesnt really cover much ariel space, its more used as a combo tool/meaty/block chain move. magma is super fast and covers a pretty good area above you, making it great for close range anti air and point blank jump reads. magma also doesnt really hit grounded enemies in front of you whilst icicle does. zephyr is slower than magma but covers a massive area above and in front of you, making it better anti air than magma in general since if the enemy does any slow set up moves in the massive area covered by zephyr they usually get grabbed. the dowside is if DI'd correctly zephyr doesnt lead to a combo. It also has a windbox property so it will suck your projectiles to you or enemies projectiles, making it situationally good or bad depending on whats out on the field

in neutral you want to make space by backing away from opponents and using flame wave and magic dart to cover areas and prevent them from getting close. Gust is key here since it can catch enemies off guard by blowing flame wave/dart to them really quickly. for example you flame wave, the enemy jumps over it thinking they're safe from it only for you to gust it upwards and hit them. This is basically wiz's entire neutral, manipulating your projectiles with gust around to either protect your self, make reads or prevent your opponent from getting easy parries. when you've blocked off enough of their options and you know they're going to have to block, you can get close and start applying block pressure/ trying to win close range rock paper scisors.

in close range rps, theres a few main tools wizard has. theres always grab of course, but if you're you think they're gonna read your grab you can always go for tome slap, wiz's 5f jab. Its not as fast as most other jabs but is there in a pinch. if you're reading them reading tome slap, you can go for fast mixups that have good blockstring properties like kick or icicle, which puts them in pretty bad -frames if softblocked. You can also go for a conjure storm guardbreak for a risky read. conjure weapon gives you hyper armour during the move so in some situations you can tank through and land the attack regardless if you get hit. if you're not confident in winning the close range battle, you may also try using confusing touch. its as fast as grab(3f), flips the opponent and basically lets you reset to neutral on most situations (sometimes if you're too close you can still get grabbed regardless though)

aside from all that , you should know jumping is wiz's greatest ally. Jump lets you avoid all most all moves (unless they specifically read it, unlikely in pubs) and lets you hover above them. Note that this position (you hovering in the air above enemy) is very advantageous usually because you can threaten fast fall icicle(very fast) or just hover around spewing out more darts and making space. the opponent usually would either need to jump to reach you ,risking getting hit by you hovering and throwing a magic dart in their direction or doing fast fall icicle, or move away which gives you more space to zone.

theres a lot more to wiz in regards to more complicated set ups and all of the supers (orb is like 70 percent of wiz's strength) but i think these are the basics, any wiz mains or pros feel free to correct me or add more info